1. Field of the Invention
The present invention relates to a method for forming a resin body, a structure for an optical waveguide, and an optical part including an optical lens.
2. Background Arts
The nano-imprint technology has been developed and progressed. Recently, the lithography applied in the integrated circuit becomes hard to clear the investment against the profitability because the exposure wavelength becomes the sub-nanometer or shorter which extremely raises the price of the exposure equipment. The nano-imprint technology has been attracted as a replaceable means for the lithography. The United States patent, U.S. Pat. No. 5,772,905, has proposed, what is called, the nano-imprint technology to form a structure with a size of nano-meter by directly pressing the mold with unevenness against the material under processed.
Roughly two types of the nano-imprint technology are known, one of which is the optical nano-imprint technology, while, the other is the thermal nano-imprint technology. Vratzov et. al has disclosed a technique relating to the optical nano-imprint, in which the resin body nano-imprinted at a room temperature is hardened by irradiating the ultraviolet rays and the mold is detached from the resin body to leave the pattern on the resin body (B/ Vratzov et al., “Large scale ultraviolet-based nanoimprint lithography,” J. Vac. Sci. Tech vol. B21(6), (2003) pp. 2760).
The Japanese Patent Application published as JP-2004-066447A has disclosed the thermal nano-imprint technology to form a substrate with holes in desired positions. This method includes steps of, preparing a mold with a plurality of projections and a substrate spin-coated with a thermoplastic resin, forming hollows transcribed from the projections in the mold by pressing the mold against the resin body at a high temperature (120° C.), solidifying the resin by cooling the temperature down to 60° C. to form the patterned resin transcribed from the pattern on the mold, exposing at least a portion of the surface of the substrate by etching the resin body, and finally, forming holes in the substrate by the anodic oxidization of the substrate. This nano-structure (holes formed in the substrate) for the fluid is to be used in the analysis and the handling of the bio-molecular such as the DNA and the protein.
Wang et al. has disclosed the nano-imprint technology applicable to the semiconductor integrated circuit (Jian Wang et al., “Fabrication of 10 nm enclosed nanofluidic channels, ” Appl. Phys. Lett., vol. 81(1) (2002) pp. 174).
The present invention is to provide a method for form a resin transcribed with a pattern with less defects from the mold by the optical nano-imprint technique.